CN109414935B

CN109414935B - Printing

Info

Publication number: CN109414935B
Application number: CN201780043397.4A
Authority: CN
Inventors: R.史密斯
Original assignee: Videojet Technologies Inc
Current assignee: Videojet Technologies Inc
Priority date: 2016-05-11
Filing date: 2017-05-04
Publication date: 2021-06-15
Anticipated expiration: 2037-05-04
Also published as: CN113360104A; EP3455077C0; US20210339538A1; EP3455077B1; US11654687B2; WO2017194913A1; GB201608285D0; US20190143704A1; EP4269115A3; US11097550B2; ES2949323T3; CN109414935A; EP3455077A1; EP4269115A2; BR112018072996A2

Abstract

An electronic data storage device for use with a cartridge for storing and dispensing liquid for use with an inkjet printer, the electronic data storage device storing print data, wherein the print data comprises at least one of: liquid density data, liquid conductivity data, recirculation data, and printer geometry data.

Description

Printing

Technical Field

The present invention relates to inkjet printing and more particularly, but not exclusively, to electronic data storage devices for use with removable cartridges for inkjet printers, such as continuous inkjet printers.

Background

In an inkjet printing system, printing consists of individual ink drops generated at a nozzle and propelled towards a substrate. There are two main systems: drop-on-demand ink, wherein ink drops are generated for printing as and when needed; and continuous inkjet printing, in which ink drops are generated continuously and only selected ink drops are directed towards the substrate, with the remainder being recirculated to the ink supply.

Continuous inkjet printers supply pressurized ink to a printhead drop generator, where a continuous stream of ink from a nozzle is broken up into individual, regular drops, for example, by an oscillating piezoelectric element. The ink drops are directed through a charge electrode where they are selectively and individually given a predetermined charge before passing through a transverse electric field provided across a pair of deflection plates. Individual charged drops are deflected by the field by an amount that depends on their charge magnitude before impacting on the substrate, while uncharged drops continue to advance without deflection and collect at a gutter from which they are recirculated to the ink supply for reuse. The charged ink drops bypass the gutter and strike the substrate at a location determined by the charge on the ink drops and the position of the substrate relative to the printhead. Typically, the substrate is moved in one direction relative to the printhead and the drops are deflected in a direction substantially perpendicular to that direction, but the deflection plates may be oriented at an angle to the perpendicular to compensate for the velocity of the substrate (movement of the substrate relative to the printhead between drop arrivals means that the rows of drops will otherwise not extend completely perpendicular to the direction of movement of the substrate).

In continuous inkjet printing, characters are printed from a matrix comprising a regular array of potential drop locations. Each matrix comprises a plurality of columns (scribe lines), each column being defined by a line comprising a plurality of potential drop locations (e.g. seven) determined by the charge applied to the drops. Thus, each usable ink droplet is charged according to the intended position in the scribe line. If a particular drop is not used, that drop is not charged and it is trapped at the gutter for recirculation. The cycle is repeated for all the dashes in the matrix and then the next character matrix is started again.

Ink is delivered under pressure to the printhead by an ink supply system that is substantially housed within a sealed compartment of a cabinet that includes a separate compartment for control circuitry and a user interface panel. The system includes a main pump that draws ink from a reservoir or tank through a filter and delivers the ink under pressure to the printhead. As ink is consumed, the reservoir is refilled as needed from a replaceable ink cartridge that is releasably connected to the reservoir by a supply conduit. Ink is fed from the reservoir to the printhead via a flexible delivery conduit. Unused ink droplets captured by the gutter are recirculated by a pump to the reservoir via a return conduit. The flow of ink in each conduit is generally controlled by solenoid valves and/or other similar components.

As the ink circulates through the system, the ink tends to thicken due to solvent evaporation, particularly in connection with recirculating ink that is exposed to air in its passage between the nozzle and the gutter. To compensate for this, "make-up" solvent is added to the ink from the replaceable cartridge as needed to maintain the ink viscosity within desired limits. The solvent may also be used to flush components of the printhead, such as nozzles and channels, during a cleaning cycle.

The ink cartridge and the solvent cartridge are filled with a predetermined amount of fluid and are substantially releasably connected to a reservoir of the ink supply system so that the reservoir can be intermittently replenished by drawing ink and/or solvent from the cartridge as needed. To ensure proper registration of the cartridge with the supply conduit, the cartridge is typically connected to the ink supply system via a docking station that includes a cartridge holder. When the cartridge is properly docked, fluid communication with the outlet port of the cartridge is ensured.

From the manufacturer's perspective, it is important that the inkjet printer consume only the correct type and quality of ink (or solvent). If a cartridge containing the wrong ink is used, print quality may be compromised and, in extreme cases, printer failure may result. Thus, in some inkjet printers, it is known to provide ink cartridges with an external machine-readable label (e.g., a barcode) that carries information about the fluid contained within the cartridge. The label is scanned past a reader associated with the control system of the printer prior to cartridge installation, and it allows ink or solvent to be drawn from the cartridge only when the control system of the printer reads the information on the label and confirms that the ink is suitable for operation with the printer.

Disclosure of Invention

It is an object of the present invention, inter alia, to provide an improved or alternative ink jet printer.

According to a first aspect of the present invention there is provided an electronic data storage device for use with a cartridge for storing and dispensing liquid for use with an inkjet printer, the electronic data storage device storing print data, wherein the print data comprises at least one of: liquid viscosity data, liquid density data, liquid conductivity data, cartridge geometry data, and printer geometry data.

By providing print data or printer/cartridge geometry data on various properties of the ink contained within the cartridge on an electronic storage device associated with the cartridge, it is possible to provide enhanced print performance. This approach avoids any risk associated with manual entry of data that is inherently unreliable and susceptible to user error. Thus, by providing print data at a storage location of the electronic data storage device associated with the cartridge, it can be ensured that this data is reliably available to the printer in use, to allow optimal control of the printer based on accurate print data.

The fluid viscosity data may include data representing the viscosity of the fluid stored within the cartridge. The liquid density data may include data representing the density of the liquid stored within the cartridge. The liquid conductivity data may include data indicative of the conductivity of the liquid stored within the cartridge. The box geometry data may include data representing the geometry of the box. The data representing the geometry of the cartridge may comprise data representing the volume of a reservoir of the cartridge. The printer geometry data may include data representing the geometry of one or more components of the printer suitable for use with the cartridge and/or the liquid contained within the cartridge.

The printer geometry data may include data representing the diameter of a printer nozzle with which the liquid contained within the cartridge is intended to be used. That is, the printer geometry data may include data representing the appropriate nozzle geometry.

The print data may include recycle data. The recirculation data may include data for controlling recirculation of air to a printhead of the printer in a manner suitable for the liquid contained within the cartridge. The recirculation data may include data representing a default level for controlling air recirculation to the printhead. The recycling data may include a humidity threshold. The humidity threshold may include data representing a humidity level above which air recirculation to the printhead should be limited for the type of ink contained within the cartridge. The recirculation data may include a temperature threshold. The temperature threshold may include data representing a temperature level above which air recirculation to the printhead should be limited for the type of ink contained within the cartridge.

The electronic data storage device may be configured to allow data write access to the predetermined data storage portion only by authorized devices.

By allowing write access only by authorized devices, printing performance can be improved by preventing data from being altered by unauthorized devices and ensuring that the data properly reflects the current state of consumable components (e.g., cartridges or filter modules) associated with the electronic data storage device. For example, a data item indicating that a cartridge is empty may be prevented from being overwritten by an unauthorized device, such that even if the cartridge is refilled (e.g., with an ink that is not authenticated for use with a particular printer, or that is different from the ink previously used with the printer), the cartridge may be prevented from being used with the printer, thereby preventing contamination of the printer by incompatible inks.

The electronic data storage device may be configured to: receiving a write request, the write request including address data associated with a predetermined data storage portion and an identifier of a writing device; authenticating the writing device based on the identifier; and writing data to said predetermined data storage portion if, but only if, said authentication indicates that said writing device is an authorized device.

There is also provided a cartridge for storing and dispensing a liquid for use with an inkjet printer, the cartridge comprising: a reservoir defining an interior space for storing a liquid; an outlet for dispensing the liquid; and an electronic data storage device according to the first aspect of the invention.

There is also provided an ink jet printer comprising a cartridge having an electronic data storage device according to the first aspect of the invention.

The inkjet printer may include a controller. The controller may be configured to receive data from the electronic data storage device and control operation of the printer based on the received data.

Controlling operation of a printer based on the received data may also include receiving sensor data, and controlling the operation of a printer based on the sensor data. That is, the printer may be controlled based on the sensor data and the reception data.

This control allows the printer to be controlled based on sensor data (e.g., temperature and/or humidity sensor data) in a manner suitable for the liquid contained within the cartridge (e.g., based on threshold data stored in an electronic storage device that indicates a suitable humidity and/or temperature level for this liquid).

The ink jet printer may be a continuous ink jet printer. The ink jet printer may be an authorized device.

According to a second aspect of the present invention, there is provided an inkjet printer comprising a controller. The printer is configured to receive a removable module comprising an electronic data storage device storing data regarding the operation of the removable module, and at least one member selected from the group consisting of: filters, fluid dampers, valves, pumps, gas sensors, drop generators, inkjet printing nozzles, piezoelectric oscillators, charging electrodes, deflection electrodes, and channels. The printer is further configured to receive at least one cartridge. A controller is configured to receive data from the electronic data storage device and to control operation of the printer based on the received data.

A removable module is intended to mean a consumable component of a printer having one or more components that perform mechanical functions and that may be prone to wear. The removable module may need to be replaced or repaired in the printer at regular maintenance cycles. A cartridge (e.g., an ink cartridge or a solvent cartridge) is not considered a removable module of a printer. However, the cartridge is a consumable component of the printer.

The removable module may include a filter module, the component being a filter, such as an ink filter.

The removable module may include a service module. The service module may include a pump, such as, for example, a flush pump. The service module may include a valve, such as, for example, a fluid control valve and/or a pressure relief valve. The service module may include a gas sensor.

The removable module may include a printing module. The print module may be referred to as a printhead. The print module may include a drop generator that includes an inkjet printing nozzle and a piezoelectric oscillator. The printing module may comprise a charging electrode and/or a deflection electrode, and/or a gutter.

The cartridge may be an ink cartridge. The cartridge may be a solvent cartridge. The cartridge may include a reservoir defining an interior space for storing the liquid and an outlet for dispensing the liquid.

The data regarding the operation of the removable module may include data regarding the status of the removable module and/or components of the removable module. The data regarding the status of the removable module and/or components of the removable module may include data representing the number of hours the removable module and/or components of the removable module have been used, or data indicating that the removable module and/or components of the removable module have exceeded a predetermined use limit.

The provision of a printer (where data is received by the controller from an electronic storage device associated with the removable module) enables the printer to be automatically configured based on the received data. For example, where removable modules are expected to have a lifetime less than that of a printer, or where they can be replaced for any reason, the electronic data storage devices associated with those removable modules may allow automatic configuration changes to be made as needed to ensure continued operation of the printer. In particular, where parameters associated with a component may differ between a particular module and an alternative for that particular module (e.g., filter life or filter usage data), the data regarding the parameters may be used to adjust the configuration of the printer in some manner (e.g., to record usage and provide an appropriate alert). By providing data to the controller of the printer, it is possible to reduce reliance on manual data entry (which is inherently unreliable) and automatically reconfigure the printer as required.

The inkjet printer may be configured to receive a plurality of removable modules, each of the plurality of removable modules including a respective electronic data storage device storing data regarding operation of a respective one of the plurality of removable modules, each of the plurality of removable modules further including a member selected from the group consisting of: filters, fluid dampers, valves, pumps, gas sensors, drop generators, inkjet printing nozzles, piezoelectric oscillators, charging electrodes, deflection electrodes, and channels.

By providing electronic data storage devices respectively associated with each of a corresponding plurality of removable modules, it will be appreciated that the likelihood of automatic configuration is increased. This is especially the case where modules may be provided in different categories.

In particular, using automatic configuration in this way allows removable modules to be provided in different categories without significantly increasing the risk of printer failure. That is, it may be desirable to provide a variety of modules, where different modules may be specifically tailored to a particular printer based on properties (such as, for example, expected usage, environmental conditions, maintenance requirements, etc.), rather than providing a single kind of module that is tailored to all printers and all uses.

The controller may be configured to receive data from each of said electronic data storage devices and to control operation of the printer based on said received data.

Controlling operation of the printer based on the received data may include configuring operation of the printer based on the received data.

At least one of the cartridges may also include an electronic memory device.

The controller may be configured to receive data from said electronic data storage device associated with at least one cartridge and to control operation of the printer based on said received data.

Controlling operation of a printer based on the received data may also include receiving sensor data, and controlling the operation of a printer based on the sensor data. That is, the printer may be controlled based on both the sensor data and the received data.

The controller may be configured to receive data from a first electronic data storage device of the at least one cartridge and a second electronic data storage device of one of the removable module or the removable module, and to control operation of the printer based on the received data.

The use of data stored in the electronic data storage device associated with both the cartridge and the replaceable module increases the number of ways in which automatic configuration and control of the printer can be provided. That is, this data may be used in combination with usage data relating to the ink pumps contained within the service modules of the ink supply system to ensure that appropriate maintenance operations are performed at convenient points in time, rather than simply providing automatic configuration with respect to cartridge volume. Alternatively or additionally, compatibility between components, for example, nozzles of a newly installed printhead and ink contained within an ink cartridge, may be checked.

The removable module or one of the removable modules and/or the electronic data storage device of the cartridge may be configured to allow data write access to the predetermined data storage portion only by authorized devices. The electronic data storage device may be configured to determine whether the controller is an authorized device and to allow data write access by the controller to the predetermined data storage address if, but only if, the controller is an authorized device.

The received data from the electronic data storage device storing data relating to the operation of the removable module may comprise data representing properties of inkjet printing nozzles associated with a printhead of the printer. Controlling operation of a printer based on the received data may include generating a modulation signal for the inkjet printing nozzles based on the received data.

For example, different nozzles may require different forms of module signaling. Thus, by providing data indicating a particular type of nozzle, it is possible to automatically control the printer based on the data stored in the electronic data storage device without having to manually reconfigure the printer when the nozzle type changes (e.g., when a new printhead is installed).

According to a third aspect of the present invention there is provided an inkjet printer configured to receive at least one consumable member, the at least one consumable member comprising: an electronic data storage device configured to store print data and further configured to allow data write access to the predetermined data storage portion only by authorized devices; the inkjet printer includes a controller; wherein the electronic data storage device is configured to: it is determined whether the controller is an authorized device and data write access to the predetermined data storage address by the controller is permitted if, but only if, the controller is an authorized device.

By allowing write access only by authorized devices, printing performance can be improved by preventing data from being changed by unauthorized devices and ensuring that the data properly reflects the current state of consumable components (e.g., cartridges or filter modules) associated with the electronic data storage device. In this way, a data item known to indicate a particular property of a box correctly reflects that property. For example, data indicating that a cartridge is empty may be prevented from being overwritten by an unauthorized device, such that even if the cartridge is refilled (e.g., with ink that is not certified for use with a particular printer, or that is different than the ink previously used with the printer), the cartridge may be prevented from being used with the printer to prevent contamination of the printer by incompatible ink. In this way, printing performance can be protected and improved.

The predetermined data storage address may be arranged to store data regarding the status of the consumable component.

The data regarding status data may include data indicating a number of hours the consumable component has been used, or data indicating that the consumable component has exceeded a predetermined usage limit.

The consumable member may comprise a cartridge for storing and dispensing a liquid for use with an inkjet printer, the cartridge comprising: a reservoir defining an interior space for storing a liquid; an outlet for dispensing the liquid; and the electronic data storage device.

The status data may include data indicative of the volume of liquid remaining in the cartridge.

The consumable component may include a filter.

The status data may include data indicating the number of hours the filter has been used.

It will be appreciated that features described in the context of one aspect of the invention may be used with another aspect of the invention. In particular, features described in the context of any of the first, second and third aspects of the invention may be used in combination with other aspects of the invention and features thereof.

Drawings

Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a schematic illustration of a continuous inkjet printer according to one embodiment of the present invention;

FIG. 2 is a schematic representation of the continuous ink jet printer of FIG. 1;

FIG. 3 is a front view of an ink cartridge for use with the printer of FIG. 1;

FIG. 4 is a perspective view of the ink cartridge of FIG. 3;

FIG. 5 is a cross-sectional side view of the ink cartridge of FIG. 3 taken along line A-A';

FIG. 6 is an exploded perspective view of an ink cartridge assembly for use with the printer of FIG. 1 and the cartridge of FIG. 3;

FIG. 7 is a schematic representation of a controller of the continuous ink jet printer of FIG. 1;

FIG. 8 is a flowchart illustrating operations performed by the continuous ink jet printer of FIG. 1; and

FIG. 9 is a flow chart illustrating a method performed by the controller of FIG. 3.

Detailed Description

Fig. 1 schematically shows an inkjet printer 1. The inkjet printer 1 includes an ink supply system 2, a printhead 3, and a controller 4. The ink supply system 2 includes an ink storage system 5 and a service module 6. In fig. 1, fluid flow through an inkjet printer is schematically illustrated by solid arrows, and control signals are schematically illustrated by dashed arrows. The service module 6 is configured to releasably engage with the inkjet printer 1 such that the module can be easily removed from the inkjet printer 1 for servicing or replacement. The service module 6 is thus a removable module for an inkjet printer.

The service module 6 comprises two cartridge connections for releasable engagement with the fluid cartridge. In particular, the service module 6 comprises a cartridge connection 7 for releasable engagement with an ink cartridge 8, and a solvent cartridge connection 9 for releasable engagement with a solvent cartridge 10. The service module 6 further comprises a printer connection 11 for releasable engagement with an inkjet printer. In use, the service module 6 forms part of the inkjet printer 1, and it will be appreciated that in this context of the expression "for releasable engagement with an inkjet printer", the term "inkjet printer" is intended to mean those parts of the inkjet printer which do not include the service module 6.

The printer connection 11 includes a plurality of fluid ports, each of which is arranged to connect to a fluid pathway within the inkjet printer 1 to allow fluid to flow between the service module 6 and other parts of the inkjet printer 1 (e.g. the ink storage system 5 and the printhead 3). The printer connection 11 also comprises electrical connectors arranged to engage with corresponding connectors on the inkjet printer 1.

Each of the cartridge connection 7 and the solvent cartridge connection 9 comprises a fluid connector for engaging an outlet of the respective cartridge 8 and solvent cartridge 10, so as to allow fluid to flow from the

cartridge

8,10 into the service module 6. Ink and solvent may flow from the service module 6 to the ink storage system 5 via the printer connection 11. In operation, ink from the cartridge 8 and solvent from the solvent cartridge 10 may be mixed within the ink storage system 5 to produce a printing ink of a desired viscosity suitable for use in printing. This ink is supplied to the print head 3, and unused ink is returned from the print head 3 to the ink storage system 5. The service module 6 is also operable to provide a flow of solvent to the print head 3 via the printer connection 11 for cleaning purposes.

The inkjet printer 1 is controlled by a controller 4. The controller 4 receives signals from various sensors within the inkjet printer 1 and is operable to provide appropriate control signals to the ink supply system 2 and the printhead 3 to control the flow of ink and solvent through the inkjet printer 1. The controller 4 may be any suitable device known in the art and typically includes at least a processor and a memory.

The ink cartridge 8 is provided with an electronic data storage device 12 that stores data about the printer 1 and the contained ink. Similarly, the solvent cartridge 10 is provided with an electronic data storage device 13 that stores data about the printer 1 and the solvent contained therein. The service module 6 may also include an electronic data storage device 14. The electronic data storage device 14 may store identification data (e.g., an identification code).

The ink storage system 5 also includes a filter module 25 (which is described in more detail below), the filter module 25 being provided with an electronic data storage device 70. The print head 3 is also provided with an electronic data storage device 71. The ink storage system 5 itself is also provided with an electronic data storage device 72. For example, the electronic storage device 72 may be provided on an ink management board (not shown). The controller 4 is arranged to communicate with electronic

data storage devices

12,13,14,70,71,72 as described in more detail below.

For example, an ink management board within the ink storage system 5 may be arranged to provide an interface between the controller 4 and each of the filter modules 25 (and associated electronic storage devices 70), service modules 6 (and associated electronic storage devices 14), cartridges 8 (and associated electronic storage devices 12), and solvent cartridges 10 (and associated electronic storage devices 13).

Referring now to FIG. 2, the ink jet printer 1 and the particular ink supply system 2 will be described in further detail. Figure 2 schematically shows elements of the inkjet printer 1 of figure 1 in more detail, and the controller 4, electronic

data storage devices

12,13,14,70,71,72 and associated signals have been omitted for clarity.

In operation, ink is delivered under pressure from the ink supply system 2 to the printhead 3 and returned via a flexible tube that is bundled with other fluid tubes and wires (not shown) into what is known in the art as an "umbilical" conduit 15. The ink supply system 2 is located in a cabinet 16, the cabinet 16 is typically desktop mounted, and the printheads 3 are disposed outside the cabinet 16.

The ink storage system 5 includes a mixing tank 17 for storing a reservoir 18 of ink, and a solvent tank 19 for storing a solvent reservoir 20 of solvent. The mixing tank has a generally conical lower portion in which a reservoir 18 of ink is disposed.

In operation, ink is drawn from the reservoir 18 of ink in the mixing tank 17 by the system pump 21. The mixing tank 17 is replenished with ink and make-up solvent from the replaceable ink cartridge 8 and solvent cartridge 10 as needed. As will be described further below, ink and solvent are delivered from the ink cartridge 8 and the solvent cartridge 10 to the mixing tank 17 via the service module 6.

As will be understood from the following description, the ink supply system 2 and the printhead 3 comprise a number of flow control valves of the same general type: a dual coil solenoid operated two-way flow control valve. The operation of the various valves is managed by a controller 4.

The ink drawn from the mixing tank 17 is first filtered by a first (relatively coarse) filter 22 downstream of the system pump 21 and then selectively delivered under pressure to two venturi pumps 23,24 and a filter module 25. The filter module 25 includes a second, relatively fine ink filter 26 and a fluid damper 27. The fluid damper 27 has a conventional configuration, and removes pressure pulsation caused by the operation of the system pump 21. Ink is supplied to the print head 3 through a feed line 28 via a pressure transducer 29.

At the printhead 3, ink from the feed line 28 is supplied to a drop generator 30 via a first flow control valve 31. The drop generator 30 includes a nozzle 32 from which pressurized ink is discharged, and a piezoelectric oscillator (not shown) that generates pressure pulsations in the ink stream at a predetermined frequency and amplitude to break up the ink stream into drops 33 of regular size and spacing. The break-up point is downstream of the nozzle 32 and substantially coincides with the charging electrode 34 (where a predetermined charge is applied to each ink droplet 33). This charge determines the degree of deflection of the ink drop 33 as the ink drop 33 passes a pair of deflection plates 35 that maintain a substantially constant electric field therebetween. The uncharged drops pass substantially undeflected to a gutter 36 from where they are recirculated to the ink supply system 2 through a return line 37 via a second flow control valve 38. The charged ink droplets are projected toward a substrate (not shown) moving past the print head 3. The position at which each drop 33 impacts on the substrate is determined by the amount of drop deflection and the speed of substrate movement.

To ensure efficient operation of the drop generator 30, the temperature of the ink entering the printhead 3 may be maintained at a desired level by a heater (not shown) before it passes to the first flow control valve 31. In the case of a printer that is started from rest, it is desirable to allow ink to flow out through the nozzle 32 without being projected toward the gutter 36 or the substrate. In this case, ink flows from the first flow control valve 31 to the nozzle 32 and then to the second flow control valve 38 via the bleed line 39, where it joins the return line 37. Whether the ink is bleed or recycled unused ink captured by the gutter 36, the passage of ink into the return line 37 is controlled by a second flow control valve 38. The returned ink is sucked back to the mixing tank 17 by the venturi pump 23.

The venturi pumps 23,24 have a known configuration and utilise bernoulli's principle whereby fluid flowing through a restriction in a conduit increases to a high velocity jet at the restriction and creates a low pressure region. If a side port is provided at the restriction, this low pressure may be used to draw in and carry away a second fluid in a conduit connected to the side port. In this case, the pressurized ink flows through a pair of conduits 40,41 and back to the reservoir 18 in the mixing tank 17. Each conduit 40,41 is provided with a

side port

42,43 at the venturi restriction. The increase in ink flow rate creates suction pressure at

side ports

42,43, and this serves to draw back the flow of ink and/or solvent via return line 37 and supply line 44, respectively.

As the ink flows through the system and comes into contact with the air in the mixing tank 17 and at the printhead 3, a portion of its solvent content tends to evaporate. The ink supply system 2 is thus operable to supply make-up solvent as needed to maintain the ink viscosity within a predetermined range suitable for use.

Service module 6 includes a body 45 defining a plurality of fluid conduits (shown schematically as lines 46 in fig. 2). The service module 6 further comprises a flush pump 47 and four

valves

48,49,50,51 arranged to selectively couple two or more of the plurality of fluid conduits 46 so as to form one or more fluid passages through the body 45. The flush pump 47 and

valves

48,49,50,51 are controlled by the controller 4 by sending one or more control signals via the printer connection 11. Using appropriate control signals, the service module 6 can be set to a variety of different configurations to allow ink or solvent to flow through the inkjet printer 1 in a variety of different modes as now described. In the following, it shall be assumed that each of the four

valves

48,49,50,51 is closed, unless stated otherwise.

In operation, ink from the cartridge 8 and solvent from the solvent cartridge 10 may be added to the mixing tank 17 as needed to produce a desired viscosity of printing ink suitable for printing. This addition of ink and/or solvent to the mixing tank 17 uses a venturi pump 24.

The mixing tank 17 is provided with a level sensor (not shown) operable to determine the level of ink in the mixing tank 17 and to output a signal indicative thereof to the controller 4. The ink is consumed during printing and therefore during normal operation the ink level in the mixing tank 17 will fall over time. When the ink level in the mix tank falls below the lower threshold, the controller 4 is operable to control the ink supply system 2 so that more ink is added to the mix tank 17. Using appropriate control signals, ink is drawn from the mixing tank 17 by the system pump 21 and delivered under pressure to the venturi pump 24 to create suction pressure at the side port 43. To add ink to the mixing tank 17, the valves 50,51 in the service module 6 are opened. Ink is drawn from the ink cartridge 8 along the supply line 44 under suction pressure from the venturi pump 24. The ink is discharged into the mixing tank 17 to raise the liquid surface. When the ink level in the mix tank 17 reaches an upper threshold, the controller 4 is operable to stop the supply of ink to the mix tank 17. To achieve this, flow to the venturi pump 24 is stopped and the valves 50,51 are closed.

After this process of replenishing the level of ink in the mix tank 17, the controller 4 sends a signal to the data storage device 12 on the ink cartridge 8 indicative of the amount of ink transferred from the cartridge 8 to the mix tank 17. The amount of ink remaining in the ink cartridge 8 may be stored on the data storage device 12 and may be updated in response to a signal from the controller 4.

As set forth above, as the ink flows through the system and comes into contact with the air in the mixing tank 17 and at the printhead 3, a portion of its solvent content tends to evaporate. The viscosity of the ink (or the amount indicating the same) inside the mixing tank 17 is periodically determined using a viscometer 52 provided in the mixing tank 17.

Viscometer 52 is periodically supplied with ink under pressure from system pump 21 via filter module 25. The flow of ink into the viscometer is controlled by control valve 53. Using the control valve 53, a predetermined volume of ink is supplied to the chamber within the viscometer 52, and then the supply of ink to the viscometer is stopped. The ink is then expelled from the chamber under gravity. The rate at which ink is discharged from the chamber depends on the viscosity of the ink and is monitored using a plurality of electrodes disposed at different levels within the chamber. Signals from the plurality of electrodes are received by the controller 4, and the controller 4 is operable to determine whether the viscosity of the ink within the mixing tank 17 is within a desired operating range defined by a lower threshold and an upper threshold.

If the viscosity is above the upper threshold, solvent is added to the mixing tank 17 from a solvent reservoir 20 in a solvent tank 19 as now described. Ink is drawn from the mixing tank 17 and delivered under pressure to the venturi pump 24 to create suction pressure at the side port 43. To add solvent, valves 49,50 in service module 6 are opened. Under suction pressure from venturi pump 24, solvent is drawn from solvent reservoir 20 along line 62 to service module 6 and along supply line 44 back to mix tank 17. The solvent drains into the mixing tank 17, reducing the viscosity of the ink in the reservoir 18.

The controller 4 may determine the amount of solvent to add to the mix tank 17 based on the determined ink viscosity. When the desired amount of solvent has been added to the mixing tank 17, flow to the venturi pump 24 may be stopped and valves 49,50 closed.

Once the solvent has been added to the mixing tank 17, the viscosity of the ink can again be determined using the viscometer 52. There may be a time delay between adding the solvent and rechecking the viscosity of the ink to allow the solvent to mix with the ink. If the viscosity is still above the upper threshold while the viscosity of the ink in the mix tank 17 is rechecked, more solvent may be added to the mix tank 17 from the solvent reservoir 20 in the solvent tank 19. This process may be repeated until the desired viscosity of the ink in the mix tank 17 is reached.

The solvent tank 19 is provided with a level sensor (not shown) operable to determine the level of solvent in the solvent tank 19 and to output a signal indicative thereof to the controller 4. The solvent is consumed during operation of the printer 1 as it is added to the mixing tank 17 to adjust the viscosity of the ink in the reservoir 18. Thus, the level of solvent in the solvent reservoir 20 in the solvent tank 19 decreases over time.

When the level of solvent in the solvent tank 19 falls below the lower threshold, the controller 4 is operable to control the ink supply system 2 so that more solvent is added to the solvent tank 19. Using suitable control signals, the

valves

48,49 in the service module 6 are opened. Solvent is drawn from the solvent cartridge 10 by the electric flush pump 47 in the service module 6 and supplied to the solvent reservoir 20 via line 62. The solvent is discharged into the solvent reservoir 20, thereby raising the liquid level.

The controller 4 is operable to stop the supply of solvent to the solvent tank 19 when the solvent level in the solvent tank 1 reaches an upper threshold. To accomplish this, flow to the flush pump 47 is stopped and the

valves

48,49 are closed.

After this process of replenishing the solvent level in the solvent tank 19, the controller 4 sends a signal to the data storage device 13 on the solvent cartridge 10 indicative of the amount of solvent transferred from the cartridge 10 to the solvent tank 19. The amount of solvent remaining in the solvent cartridge 10 may be stored on the data storage device 13 and may be updated in response to a signal from the controller 4.

The make-up solvent provided from the solvent cartridge 10 is also used to flush the printhead 3 at appropriate times to keep it free of clogging (as now described). Ink is drawn from the mixing tank 17 and delivered under pressure to the venturi pump 23 to create suction pressure at the side port 42. The solvent is drawn from the solvent cartridge 10 by an electric flush pump 47 in the service module 6 and supplied to the print head 3 through a flush line 54 via a filter 55. The flow of solvent from the service module 6 to the printhead 3 is controlled by a first flow control valve 31.

A pressure relief valve 56 is connected across the inlet and outlet of the flush pump 47 and serves to relieve excess pressure on the suction side of the flush pump 47. For example, the pressure relief valve 56 may be arranged to maintain a desired pressure, e.g. 2.5 bar, downstream of the flush pump 47.

The solvent flows to the nozzle 32 via the first flow control valve 31. After passing through the nozzle 32 and into the channel 36, the solvent (along with dissolved ink from the print head 3) is drawn into the nozzle 32 under suction pressure from the venturi pump 23. The solvent and ink are drained into the mixing tank 17.

As set forth above, the flow of ink and solvent into the mixing tank 17 is accomplished using the venturi pump 24, which requires a minimum amount of fluid in the mixing tank 17. If there is insufficient fluid in the mixing tank 17 to operate the venturi pump 24 (e.g., before the ink supply system 2 is first used), the flush pump 47 in the service module 6 may be used to fill the mixing tank 17 with fluid by adding fluid thereto.

To fill the mixing tank 17, the cartridge is engaged with the solvent cartridge connection 9. To add ink to the mixing tank 17, the valves 48,50 in the service module 6 are opened. Ink is drawn from the cartridge (in the solvent cartridge connection 9) by an electric flush pump 47 in the service module 6 and supplied to the mixing tank 17 through the supply line 44 via the side port 42. Once a sufficient amount of ink has been added to the mixing tank 17, the flush pump 47 is stopped and the valves 48,50 are closed.

In use, the atmosphere in the mixing tank 17 and the solvent tank 19 may become saturated with solvent. A condenser unit 57 is provided in an upper portion of the solvent tank 19. The condenser unit 57 may include a peltier-type condenser, for example.

A vent tube 58 is provided between the mixing tank 17 and the solvent tank 19 to allow air to flow therebetween. The vent tube 58 is arranged such that it couples the space above the reservoir 18 of ink to the space above the solvent reservoir 20. Solvent laden vapor from the mixing tank 17 enters the solvent tank 19 via vent line 58. The air from the mix tank 17 is warmer than the air in the solvent tank (due to the action of the system pump 21) and so the air from the mix tank 17 rises via the vent line 58 to the top of the solvent tank where it enters the condenser unit 57.

As the air contacts the active elements within the condenser unit 57 and is cooled, the solvent condenses. The condensate (solvent) drains to the solvent reservoir 20. Dry air (from which solvent has been removed) enters the common port of the three-way control valve 59. As now described, the air flow through the system may be controlled using a control valve 59.

The drying air from the condenser unit 57 may flow through the outlet duct 60, via the outlet duct 60, the drying air being discharged to the air space within the printer cabinet 16. The air flow path may be a default configuration for the control valve 59.

Alternatively, the dry air from the condenser unit 57 may flow through the conduit 61, the conduit 61 passing through the umbilical 15 to the print head 3. Near the channel 36, the line 61 ends in the print head 3 at the return line 37. The vacuum pressure draws the vented air (along with any ink entering the gutter 36) along the return line 37 towards the second flow control valve 38. Normal operation of the venturi pump 23 draws unused ink droplets and expelled air along the return line 37, through the umbilical cord 15 and back to the side port 42. Both the unused ink and the discharged air are discharged into the mixing tank 17.

When the control valve 59 is used to direct the drying air from the condenser unit 57 through the line 61, a 'closed' hydraulic ring is created. Any solvent vapor not recovered by the condenser unit 57 is passed back to the mixing tank 17 via

lines

61,32 and thus the loss of solvent from the inkjet printer 1 is minimized. The system continuously recirculates the same air, which prevents (or at least minimizes) inflow of ambient air that would otherwise enter via the channel 36 (e.g., if the control valve 59 vented dry air from the condenser unit 57 to the air space within the printer cabinet 16 via the outlet duct 60). This prevents ambient air from entering the system and helps prevent oxygen uptake via the channels 36, which in the long term promotes improved ink performance by reducing the probability of ink oxidation.

In some embodiments, the service module 6 may also be a gas sensor 87 operable to determine the presence or level of a gas (e.g., solvent vapor) within the cabinet 16. Gas sensors can become "poisoned" over time and therefore generally have a limited useful life, after which they need to be replaced.

The service module 6 provides an interface between the ink jet printer 1 and each of the ink cartridges 8 and the solvent cartridge 10, allows fluid to flow from each

cartridge

8,10 to the ink jet printer, and provides an electrical coupling between the ink jet printer 1 and each

cartridge

8, 10. Since the printer connection 11 provides a releasable engagement with the inkjet printer, the service module 6 can be easily removed from the inkjet printer 1 for repair or replacement. In general, such maintenance or replacement will be performed at a replacement rate that is different from the replacement rate of the

fluid cartridges

8,10 or other replaceable components of the printer 1. This is advantageous because during operation of the inkjet printer 1, one or more of the plurality of conduits 46,

valves

48,49,50,51 and flush pump 47 may be blocked or damaged, or the gas sensor 87 may reach the end of its useful life.

Fig. 3 to 5 show the ink cartridge 8 in more detail. It will be appreciated that the description of the ink cartridge 8 is also applicable to a substantially similar solvent cartridge 10. The cartridge 8 has a volume of about 1000 ml and is suitably formed by blow moulding from a thermoplastic material. For example, the thermoplastic material may be a high density polyethylene resin.

Cartridge 8 includes a reservoir 80 enclosing an interior space for storing liquid, and an outlet 81 for dispensing liquid from reservoir 80 to ink supply system 2. The outlet 81 may be provided with a fluid-tight seal or valve (not shown) which forms a fluid-tight engagement with the cartridge connection 7 of the ink supply system.

The reservoir 80 is generally box-shaped. The inner space of the reservoir 80 is defined by a first face wall 82 (see fig. 5), a second face wall 83 (see fig. 5), and a peripheral wall 84 (see fig. 4). The first and

second walls

82,83 are on opposite sides of the reservoir 80. A peripheral wall 84 connects the first and second boundaries of the

walls

82, 83. Suitably, the peripheral wall has a width defined by the spacing between the first 82 and second 83 panels. The area of each of the

face walls

82,83 is greater than the area of the peripheral wall 84 of the reservoir 80. The width of the perimeter wall 84 is less than the width W of the reservoir 80 (e.g., the width of the perimeter wall 84 may be less than 50% of the width W). As shown in fig. 5, the two

face walls

82,83 are substantially parallel to each other.

In order to control the spacing S (see fig. 5) between the two opposing

face walls

82,83, a reinforcing structure 85 is provided. As shown in fig. 3 and 5, the reinforcing structure 85 is centrally located along the length L of the reservoir, forming a waist portion of the reservoir 80. The reinforcing structure 85 preferably does not protrude beyond the outer boundary of the reservoir 80 defined by the

face walls

82,83 and the peripheral wall 84.

As shown in fig. 3,4 and 5, the reinforcing structure 85 divides the interior space of the reservoir 80 into a first chamber 86 and a second chamber 87. As further shown in fig. 3 and 4, the reinforcing structure 85 provides a

fluid communication path

88,89 between the

chambers

86, 87. The reinforcing structure 85 has an aperture 90 through the reservoir 80.

The reinforcing structure 85 reinforces the reservoir 80 to reduce expansion deformation of the reservoir 80 when filled with liquid. This allows the reservoir 80 to have a high capacity. Specifically, the reinforcing structure 85 extends between the first and

second face walls

82,83, and thus prevents the spacing S between the

face walls

82,83 from exceeding a predetermined upper limit. Thus, the degree of distortion or deformation (e.g., expansion or aeration) experienced by the reservoir 80 when filled with a large volume of liquid is reduced.

In use, the cartridge 8 may be enclosed within the housing 91 to form the cartridge assembly 92. As shown in fig. 6 in connection with the cartridge 8, the housing 91 comprises two

parts

91a,91b which may be releasably joined together by a snap fit or other suitable means. The electronic data storage device 12 associated with the cartridge 8 may be mounted within a slot 93 provided by the housing 91. The housing 91 has a shape that is substantially similar to the shape of the cassette received therein and may provide additional structural support to the cassette 8, particularly the reinforcing structure 85. Thus, the housing 91 may help limit the degree of distortion or deformation, e.g., expansion or inflation, experienced by the reservoir 80.

It will of course be appreciated that the cassette 8 may take other forms, such as, for example, the form described in european patent No. 2,195,168.

The configuration and operation of the controller 4 and the electronic

data storage devices

12,13,14,70,71,72 will now be described in more detail. In use, the controller 4 communicates with each of the

electronic storage devices

12,13,14,70,71,72 in order to maintain proper operation of the printer 1. Fig. 7 shows the controller 4 in more detail. It can be seen that the controller 4 includes a CPU 4a configured to read and execute instructions stored in a volatile memory 4b in the form of random access memory. The volatile storage 4b stores instructions executed by the CPU 4a and data used by those instructions. For example, in use, data regarding an image printed by the printer 1 (image data) or printer configuration or control data (print data) may be stored in the volatile memory 4 b.

The controller 4 also includes non-volatile storage in the form of a hard disk drive 4 c. Of course, other forms of non-volatile storage may be used. The image and/or print data may be stored on the hard disk drive 4 c. The controller 4 also includes an I/O interface 4d, to which peripheral devices used in conjunction with the controller 4 are connected. More specifically, the display 4e is configured so as to display an output from the controller 4. For example, the display 4e may display a control interface for the printer 1. The input device is also connected to the I/O interface 4 d. For example, this input device may include a touch screen interface associated with the display 4e to allow user interaction with the controller 4. The network interface 4f allows the controller 4 to connect to a suitable computer network for receiving and transmitting data from and to other computing devices. The CPU 4a, the volatile storage 4b, the hard disk drive 4c, the I/O interface 4d, and the network interface 4g are connected together by a bus 4 g.

The controller 4 further includes an authentication device 4 h. The authentication device 4h is connected to the CPU 4a by a bus 4 g. The authentication device 4h is a secure authentication and verification device such as, for example, an ATSHA204 CryptoAutomation device manufactured by Atmel Corporation in the United states. Authentication device 4h is via a serial data connection (e.g., I²C interface) to communicate with the CPU 4 a. However, it will be appreciated that alternative secure authentication and verification devices may be used and may communicate with the CPU 4a in a different manner (e.g., via the I/O interface 4 d).

The I/O interface 4d allows communication between the controller 4 and the various

electronic storage devices

12,13,14,70,71, 72. This communication may use, for example, the I2C interface.

Further, as described above, the electronic

data storage devices

12,13 associated with the

cartridges

8,10 are in communication via the service module 6. The cartridge connection part 7 and the solvent cartridge connection part 9 thus each comprise an electrical contact arranged to contact a corresponding contact on the engaged cartridge 8 or solvent cartridge 10. The corresponding contacts on the

cartridges

8,10 allow reading and/or writing information from/to the

data storage devices

12,13, respectively, via the printer connection 11 of the service module 6. Electrical connections (not shown) are also disposed between the controller 4 and each of the

electronic storage devices

14,70,71, 72.

In use, communication between the controller 4 and the various

electronic storage devices

12,13,14,70,71,72 is performed in such a way that: such that the controller can authenticate the consumable component with which the electronic storage device is associated. The electronic storage devices are security authentication and verification devices, respectively, such as, for example, the ATSHA204 CryptoAutomation device manufactured by Atmel Corporation of the United states. However, it should be appreciated that alternative secure authentication and verification devices may be used to provide authentication. The data stored on each of the

electronic storage devices

12,13,14,70,71,72 will now be described in more detail.

The electronic storage device 12, which is associated with the cartridge 8, stores data that may be useful in order to ensure a lasting optimal operation of the printer 1. The data stored on electronic storage 12 may be generally referred to as "print data". That is, the stored data generally relates to printing. The types of data stored within the electronic data storage device 12 are described in more detail below. Similarly, the electronic data storage device 13 associated with the solvent cartridge 10 stores data regarding the solvent contained (e.g., the type and amount of solvent). Further, the electronic data storage 14 within the service module 6 may store data (e.g., authentication data) about the service module 6.

In more detail, in an embodiment, the electronic storage device 12 stores data about the cartridge 8 itself, such as, for example, data allowing the cartridge to be uniquely identified (e.g., alphanumeric data), data specifying the volume of the cartridge, data about the relationship between the cartridge and other cartridges that may be packaged together, the shelf life of the cartridge, and the production lot number of the cartridge. The electronic storage device 12 also stores data about the ink stored within the cartridge 8, such as, for example, data about one or more of: the type of ink contained within the cartridge (e.g., whether the ink is a dye and/or pigment based ink and/or a food grade ink); how the ink should be used (e.g., whether any form of agitation is required prior to use); the amount of ink stored in the cartridge 8; and the properties of the ink stored within the cartridge 8. Such properties of the ink may include, but are not limited to, viscosity of the ink, density of the ink, conductivity of the ink. The electronic storage device 12 also stores data regarding other aspects of the printer 1 and its interaction with the ink and/or cartridge 8, such as, for example, data regarding the type of replenishment solvent suitable for use with the ink, data regarding the temperature of the print head, the appropriate nozzle size for use with the ink, and data regarding the type of printer with which the ink and/or cartridge is compatible.

The electronic storage device 12 may also store data regarding air recirculation within the printhead. For example, electronic storage device 12 may store data representing default levels (e.g., air flow rates or flow valve set points) for controlling air recirculation to the printhead. The electronic storage device 12 may also store a humidity threshold that represents a humidity level above which recirculation of air to the printhead should be limited for the type of ink contained within the cartridge. The electronic storage device 12 may also store a temperature threshold that represents a temperature level above which air recirculation to the printhead should be limited for the type of ink contained within the cartridge.

It has been recognized that by providing data regarding various properties of ink contained within the cartridge 8 on an electronic storage device 12 associated with the cartridge 8, it is possible to provide enhanced printing performance. This approach avoids any risk associated with manual data entry of properties (e.g., viscosity, density, or conductivity of the ink). It should be recognized that this process of manual data entry is inherently unreliable and susceptible to user error.

Thus, by providing data relating to the density of ink contained within an ink cartridge at a memory location of an electronic data storage device associated with the cartridge, it can be ensured that this data is reliably available to the printer in use, thereby allowing optimal control of the printer based on accurate ink density data. Similarly, by providing data regarding the viscosity of ink contained within an ink cartridge at a memory location of an electronic data storage device associated with the cartridge, it can be ensured that this data is reliably available to the printer in use, thereby allowing for optimal control of the printer based on accurate ink viscosity data. Further, data regarding ink density may be used to generate data representing ink viscosity. As described above, viscometer 52 may be used to generate a quantity indicative of the viscosity of the ink. However, it should be recognized that data regarding ink density may also be used to generate data representing the viscosity of the ink. Specifically, the data regarding ink density may be combined with data generated by the viscometer 52 to generate data representing ink viscosity. Further, the data regarding the viscosity of the ink may include various coefficients that represent the relationship between the viscosity measure of the ink and the temperature.

Furthermore, by providing data regarding the conductivity of the ink contained within the ink cartridge at a reservoir location of an electronic data storage device associated with the cartridge, it can be ensured that this data is reliably available to the printer in use, thereby allowing optimal control of the printer based on accurate ink viscosity data.

Furthermore, it has also been recognized that by providing data regarding cartridge geometry on the electronic data storage device 12 associated with the cartridge 8, it is possible to provide enhanced printing performance. In addition, this approach avoids manual entry of data about the cartridge 8 (such as, for example, cartridge volume), which is inherently unreliable and susceptible to user error. It will therefore be appreciated that by providing data relating to the volume of the ink cartridge in a memory location of the electronic data storage device 12 associated with that cartridge 8, it can be ensured that this data is reliably available to the printer 1 in use, thereby allowing optimal control of the printer 1 based on accurate cartridge volume data, as described in more detail below.

Furthermore, it will also be appreciated that by providing data regarding the geometry of aspects of the printer 1 suitable for use with ink contained in the cartridge 8, it is possible to provide enhanced printing performance. In addition, with respect to data on geometry (such as, for example, print head nozzle (or orifice) size), this process is inherently unreliable and susceptible to user error. It will therefore be appreciated that by providing data relating to printer geometry (e.g. nozzle size) at a memory location of the electronic data storage device 12 associated with that cartridge 8, it can be ensured that data is reliably available to the printer 1 in use, thereby allowing optimal control of the printer 1 based on accurate information about the appropriate nozzle size. For example, if an incorrect nozzle size is used, the nozzles may clog, resulting in downtime while cleaning is performed and requiring adjustments to printer settings. Thus, by providing this printer geometry data (reliably) to the printer 1, this downtime can be avoided or at least reduced.

The electronic storage device 12 also stores data regarding the continued use of the cartridge 8, such as, for example, the volume of ink left in the cartridge 8, and the number of times the cartridge 8 has been inserted into the printer (number of insertions). Data regarding the volume of ink remaining within cartridge 8 may be updated based on measurements made of how much fluid was used during the printing operation. For example, measurement of the volume of fluid extracted from the cartridge 8 may be performed by any convenient and well-known technique. This measurement may be used in combination with data indicative of the volume of the cartridge (which is stored in electronic storage 12) to accurately determine the volume of ink remaining within the cartridge 8. Further, this data can be used to provide an accurate indication of the number of hours of operation, which can be expected based on the remaining volume of ink within the cartridge. In this manner, the use of cartridge geometry data stored on the electronic storage device 12 may allow the operation of the printer 1 to be improved, for example, by allowing refilling of ink to be scheduled at a convenient time. For example, if it is determined that there is insufficient ink remaining for the duration of the planned production run, the ink cartridge may be replaced before the start of the particular production run, thereby avoiding any interruption of the planned operation.

The data items described above may be stored in a write-only storage area of the electronic data storage device 12 or a read-write storage area of the electronic data storage device 12. It will be appreciated that data items that are fixed at the time of manufacture of the cartridge 8 (e.g., cartridge identification or ink type) are stored in the write-only storage area. On the other hand, the changed data items (e.g., remaining ink volume, number of cartridge insertions) are stored in the read-write memory section during use of the cartridge 8, and are preset to initial values during manufacture.

In a similar manner, the electronic data storage 13 stores data about the solvent cartridge 10, such as, for example, data that allows the cartridge 10 to uniquely identify (e.g., alphanumeric data), data specifying the volume of the cartridge 10, the shelf life of the cartridge 10, and the production lot number of the cartridge 10. The electronic data storage 13 may also store data regarding the solvent stored within the cartridge 10, such as, for example, the type of solvent stored within the cartridge 10. The electronic data storage device 13 also stores data regarding the continued use of the cartridge 10, such as, for example, the volume of solvent remaining within the cartridge 10, and the number of times the cartridge 10 is inserted into the printer, which may be stored in a read-write portion of the electronic data storage device 13.

When the ink supply system 2 is first used, data from the electronic data storage device 12 and/or the electronic data storage device 13 is read to ascertain the type of ink and/or solvent used. Subsequently, when a new cartridge or solvent cartridge is used within the printer 1, the data stored on the respective electronic

data storage devices

12,13 of the cartridge 8 and solvent cartridge 10 may be checked by the controller 4 to ensure compatibility. In this manner, when the ink supply system 2 is used with a particular type of ink, the controller 4 ensures that the printer 1 is operational (i.e., ensures that ink is allowed to flow from the ink cartridge 8 and/or solvent is allowed to flow from the solvent cartridge 10) only if the data associated with the ink cartridge 8 and/or the solvent cartridge 10, as stored on the electronic

data storage devices

12,13, indicates compatibility.

As briefly described above, the electronic data storage device 14 within the service module 6 may store identification data. The electronic data storage device 14 also stores other types of data, such as identification data about the type of ink and/or solvent with which the service module 6 may be used (or has been previously used), data indicating technical information about the service module itself (e.g., service module type), data indicating the type of the flush pump 47, data indicating the type of the

valves

48,49,50,51, data regarding the characteristics of the gas sensor 87 (e.g., calibration or deviation data), the model number of the service module 6 or inkjet printer 1, serial number, manufacturing date, expiration date, date first put into use, the number of hours the service module 6 has been used in the inkjet printer 1, service life, and the like.

The electronic data storage device 14 may also include a writable data portion. The ink jet printer 1 can write to the electronic data storage device 14 to indicate that the service module 6 has reached the end of its useful life, so that the service module is no longer available to the ink jet printer 1 or any other printer.

In a manner similar to

electronic storage devices

12,13,14, electronic storage device 70 associated with filter module 25 also stores data associated with filter module 25. For example, in an embodiment, the electronic storage device 70 stores data regarding the filter manufacturing date and rating (in terms of granularity). The electronic storage device 70 also stores data regarding the use of the filter, such as, for example, the number of insertions, and the type of ink with which the filter is used. The ink jet printer 1 can write to the electronic data storage device 70 to indicate that the filter module 25 has reached the end of its useful life so that the filter module 25 is no longer available to the ink jet printer 1 or any other printer.

An electronic storage device 71 associated with the print head 3 stores data about the print head 3. For example, in an embodiment, the electronic storage device 71 stores data regarding the printhead type and geometry (e.g., printhead mounted (built up) sensor presence, printhead nozzle size, printhead deflector plate type, printhead deflector plate size, printhead deflector plate gap, last chance filter details (if any), printhead drop generation frequency, printhead manufacturing date). The electronic storage device 71 also stores data relating to the use of the printhead 3 such as, for example, the number of insertions and the cumulative total number of drops deflected by the printhead in use. The ink jet printer 1 can write to the electronic data storage device 71 to indicate that the printhead 3 has reached the end of its useful life so that the printhead 3 is no longer available to the ink jet printer 1 or any other printer.

The electronic storage device 72 associated with the ink storage system 5 stores data about the ink storage system 5 itself, such as, for example, about the manufacture and assembly of various components of the ink storage system 5 (e.g., an ink management board). More generally, the electronic storage device 72 may store data regarding the ink supply system 2 and the printer 1 as a whole. For example, in an embodiment, the electronic storage device 72 stores data regarding the use of the ink storage system 5, such as, for example, the number of hours the ink storage system 5 has been used, data regarding the number of hours the ink pump 21 has been used.

For example, the electronic storage device 72 may also store data regarding the operation of the ink cartridge 8, the solvent cartridge 10, the service module 6, the filter module 25, and the printhead 3. In an embodiment, the electronic storage device 72 stores data (e.g., alphanumeric data) that allows the ink and/or solvent cartridge to be uniquely identified, data specifying the volume of the ink and/or solvent cartridge, data regarding the relationship between the ink and other cartridges that may be packaged together, the shelf life of the ink cartridge, and the production lot number of the cartridge. The electronic storage device 72 also stores data about the ink stored within the cartridge 8, such as, for example, data about one or more of: the type of ink contained within the cartridge (e.g., whether the ink is a dye and/or pigment based ink and/or a food grade ink); how the ink should be used (e.g., whether any form of agitation is required prior to use); the amount of ink stored in the cartridge 8; and the properties of the ink stored within the cartridge 8. Such properties of the ink may include, but are not limited to, viscosity of the ink, density of the ink, conductivity of the ink. The electronic storage device 72 also stores data regarding other aspects of the printer 1 and its interaction with the ink and/or cartridge 8, such as, for example, data regarding the type of replenishment solvent suitable for use with the ink, data regarding the print head temperature and the appropriate nozzle size for use with the ink.

It will be appreciated that the data stored by one of the

electronic storage devices

12,13,14,70,71,72 described above may be a copy of the data stored on another one of the electronic storage devices. For example, where the electronic storage device 72 stores data about the cartridge 8, the data may have been copied from the associated storage location of the electronic storage device 12.

In general, the electronic

data storage device

12,13,14,70,71,72 may include security properties such that only suitable or recognized components (e.g., consumable components) may be used with the inkjet printer 1 and/or such that only suitable or recognized printers or devices have full access to data stored within the electronic

data storage device

12,13,14,70,71,72 for use with the electronic

data storage device

12,13,14,70,71, 72.

It will be appreciated that where components are expected to have a useful life less than that of the printer 1, or they may be replaced for any reason, the electronic data storage devices associated with those components may allow automatic configuration changes to be made as required to ensure continued operation of the printer 1. In particular, where parameters associated with a component (e.g., cartridge capacity, volume of ink remaining, filter life, or filter usage data) may differ between a particular component and a replacement for that particular component, the data regarding the parameters may be used to adjust the configuration of the printer in some manner (e.g., record usage and provide an appropriate alert). Thus, by providing data to the printer 1 as described above, it is possible to reduce reliance on manual data entry (which is inherently unreliable as set out above) and automatically reconfigure the printer 1 as required.

In an embodiment, compatibility between components, for example, nozzles of a newly installed printhead and ink contained in an ink cartridge, may be checked. It will be appreciated that such compatibility is necessary for optimal operation of the printer, and by controlling the printer so as to prevent operation with incompatible components, damage to the printer (or components thereof) may be prevented.

Further, by providing electronic data storage devices associated with multiple ink supply system components (especially where those components may be provided in different categories), it will be appreciated that the potential for automatic configuration is increased. The use of automatic configuration achieved in this way allows components to be provided in different kinds without significantly increasing the risk of printer failure. That is, it may be desirable to provide multiple components, where different components may be specifically tailored to a particular printer based on properties (such as, for example, expected usage, environmental conditions, maintenance requirements, etc.), rather than providing a single kind of component that is tailored to all printers and all uses. However, without automatic configuration being feasible, if the relevant data segments are manually entered into the printer, individual deviations from the standard components can lead to malfunctions. Accordingly, by providing an electronic data storage device associated with each of several printer components, reliable operation of the printer may be improved.

In some embodiments, data stored within electronics 71 associated with printhead 3 may provide information regarding the type of print nozzles within printhead 3 and/or the type of deflector plate within printhead 3. This information may be used by the controller to ensure that the printer 1 operates correctly according to those subcomponents (e.g., by providing appropriate charging and stimulation signals and/or ink pressure). For example, the modulation signal applied to the nozzles has a fixed frequency for some nozzle types and a variable frequency for other nozzle types. Suitable nozzle modulation algorithms for generating the modulation signal applied to the nozzles may thus be chosen based on data regarding the type of print nozzle.

In this way, the print head 3 may be replaced by an alternative print head having a different type or configuration, and any risk of incorrect operation due to incorrect configuration settings may be minimized.

In some embodiments, data representing the type of ink contained within the ink cartridge 8 obtained from the electronic storage device 12 may be used in combination with sensor data received by the controller 4 from one or more sensors contained within the printer 1 to optimize or improve printer control.

For example, the ink type data may be combined with temperature data and/or humidity data in order to maintain proper operation. For example, some types of ink are more hygroscopic than others, so the printer may be arranged to monitor temperature and/or humidity. Depending on the detected temperature and/or humidity level, the recirculation of air to the print head may be moderately controlled. For example, if the temperature and/or humidity level exceeds a respective threshold level (which may be stored on electronic storage device 12), new air may be reduced from entering the system. In this way, control of air recirculation may be based on a combination of monitored temperature, monitored humidity level, and data associated with ink contained within the cartridge.

The authentication process performed by the printer 1 to authenticate a consumable member (e.g., the ink cartridge 8 having the electronic storage device 12) and utilizing the security features briefly described above will now be described in detail with reference to fig. 8. At step S1, the ink cartridge 8 is physically connected to the connection portion 7 of the service module 6. At step S2, the controller 4 executes an authentication process during which a determination is made as to whether the ink cartridge 8 is deemed authentic (authetic). If the ink cartridge 8 is regarded as authentic, the process proceeds to step S3, where a normal printing operation is performed at step S3. If the ink cartridge 8 is not regarded as authentic, the process proceeds to step S4, and at step S4, the printing operation is prevented, and the user is notified that the mounted ink cartridge 8 is not an authentic cartridge. If a new consumable component (e.g., cartridge, filter module, print head, service module) is detected, the process begins again at step S1.

The authentication process performed at step S2 is arranged to ensure that only authentic consumable components are allowed to be used with the printer 1. The authentication process utilizes a Message Authentication Code (MAC) generated by the electronic storage device (e.g., electronic storage device 12) and this MAC is compared to a MAC generated by an authentication device 4h associated with controller 4. If the two MACs are consistent, authentication is complete, and if not, the consumable component is not considered authentic.

The MAC itself may be generated in many ways and may be based in some way on a user-defined secret, a static internal key, or a challenge provided by the authentication device 4 h. In addition, each electronic storage device has a unique serial number (some of which bits may be configured to be associated with a particular manufacturer). The MAC is generated by providing data to a secure hash algorithm (SHA-256) engine contained within the authentication device 4h or the electronic storage device. The generated MAC includes a 256-bit code. The authentication may be based on various challenge techniques, such as, for example, fixed challenge authentication, unique challenge authentication, random challenge authentication, or diversified key authentication.

In one embodiment, diversified key authentication is used. The processing steps performed to provide this authentication are now described with reference to fig. 9, and are performed during step S2 as described above with reference to fig. 8. The process begins at step S10, where at step S10, controller 1 identifies a consumable component (e.g., by reading a serial number stored within a storage location of electronic storage device 12). The process then proceeds to step S11, and at step S11, an encryption calculation is performed in the authentication apparatus 4h based on the obtained serial number and the root key securely stored in the authentication apparatus 4 h. The cryptographic calculation replicates the diversified keys stored within the electronic storage device 12.

The process then proceeds to step S12, and at step S12, the authentication device 4h generates a random number challenge. The challenge is passed to the SHA-256 engine within the authentication device 4h, along with the diversified keys generated at step S11, which generates a response (or digest) at process step S13. The process then proceeds to step S14, where in step S14 the random number challenge is communicated to the electronic storage device 12 within the consumable component. At process step S15, the SHA-256 engine within the electronic storage device 12 receives the random number challenge and also receives a version of the diversified key stored within the electronic storage device 12 and generates a response (or digest). At process step S16, the generated response is returned to the authentication device 4h, and then the process goes to step S17, at step S17, the authentication device 4h performs a comparison to determine whether the response generated by the electronic storage device 12 matches the response (digest) generated within the authentication device 4 h. If the responses match, the authentication is successful, and the process returns to step S3 of FIG. 8. On the other hand, if the responses do not match, the authentication is unsuccessful, and the process returns to step S4 of fig. 8.

Of course, it will be recognized that the authentication process described above is one way in which authentication may be performed, and that alternative techniques may be used. Further, the authentication process may be selected based on the type of secure authentication and verification device selected, or vice versa.

Once authentication is (successfully) performed, other data items may be retrieved from storage locations within the authenticated electronic storage device 12 and used to control the operation of the printer 1 as described in more detail above.

A similar authentication process may be performed by the printer 1 to authenticate each consumable component installed. Authentication may then be performed at any convenient interval (e.g., at startup or at a configuration change).

It will be appreciated that some of the data items stored within the

electronic storage devices

12,13,14,70,71,72 are expected to be unchanged after manufacture and therefore do not require editing. However, as described above, some data items (e.g., data regarding continued use of the cartridge, such as, for example, the volume of solvent remaining within the cartridge) may change during use and thus may be stored in the read-write portion of the electronic data storage device 12.

However, the controller 4 and the electronic data storage device 12 communicate in such a way that: to ensure that only authorized devices (e.g., printers or authorized manufacturing devices) have write access to those data items, rather than allowing free read write access to such data items that may change during operation. It has been recognised that if consumable components (

e.g. cartridges

8,10, filter module 25, service module 6) that are required to be used with the printer 1 are not protected in this way, it is possible to modify the data stored on the electronic data storage device of the consumable component so that it does not correctly reflect the contents or status of this component, and for those components that are not suitable for use with the printer, the print quality is reduced and damage to the printer may be caused. Thus, data writing to a predetermined storage area within the electronic data storage device 12 is only permitted when the electronic data storage device 12 is connected to an authorized printer 1 (or another authorized device, such as during manufacture).

It will be appreciated that a similar process may also be used to protect predetermined storage areas within the electronic

data storage device

13,14,70,71 associated with various other consumable devices.

It will also be appreciated that the consumable component should be replaced if it has reached the end of its useful life. For example, the filter module 25 has a lifetime in hours (e.g., about 5000 hours). Any use beyond this duration may result in an increased risk of the filter becoming clogged and failing to provide the correct ink flow to the printhead. Similarly, for example, the service module 6 may have a lifetime in hours of use (e.g., approximately 12,000 hours). Use beyond this time may increase the risk of ink blockage, pump failure, or other failure modes.

Ink cartridges and solvent cartridges may be considered to be at the end of their useful life when the fluid contained therein has been depleted. Of course, it will be appreciated that refilling the cartridge may result in incompatible inks (or solvents) being used with the printer 1, and associated problems (e.g., contamination of the fluid lines or other consumable components, and consequent degraded printing). Thus, by preventing writing to a particular data storage area by an unauthorized device, it is possible to prevent any such problems due to the use of incompatible inks or solvents.

Thus, the printer 1 may also be configured to become inoperable if a data item stored within the electronic data storage device associated with the consumable component indicates that the consumable component has reached the end of its useful life. If it is possible to override the relevant data item in the electronic data storage to indicate that further use of the consumable component is possible, the consumable component may be used accidentally while it is in a state that may cause damage to other system components. Thus, by providing a data storage area in an electronic storage device that can only be written via an authorized device (e.g., printer 1), it is possible to prevent such incorrect operation, and thus reduce the risk of damage to printer 1 (or its constituent/other consumable components) and provide more reliable printing performance.

In some embodiments, the information stored on any of the electronic

data storage devices

12,13,14,70,71 may be stored in encrypted form. This may prevent access (even read access) to the data by unauthorized devices.

In the foregoing description, reference has been made to the controller 4 described with reference to fig. 7. Various functions of the controller 4 have been characterized. It will be appreciated that the controller 4 may be implemented in any convenient manner, including as an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or a microprocessor connected to a memory storing processor readable instructions, the instructions being arranged to control the printer, and the microprocessor being arranged to read and execute the instructions stored in the memory. Further, it will be appreciated that in some embodiments, the controller 4 may be provided by a plurality of controller devices, each of which is responsible for performing some of the control functions characterized by the controller 4.

While specific embodiments of the invention have been described above, it will be appreciated that the invention may be practiced otherwise than as described, and that the described embodiments are intended to be illustrative, not limiting, in all respects. Various modifications may be made to the embodiments described without departing from the spirit and scope of the invention.

Claims

1. An electronic data storage device for use with a cartridge for storing and dispensing liquid for use with an inkjet printer, the electronic data storage device storing print data, wherein the print data comprises at least one of: recycle data and printer geometry data;

wherein the recirculation data comprises data for controlling recirculation of air to a printhead of the inkjet printer in a manner appropriate for the liquid contained within the cartridge.

2. The electronic data storage device of claim 1, wherein printer geometry data comprises data representing a geometry of one or more components of the inkjet printer adapted for use with the cartridge and/or the liquid contained within the cartridge.

3. The electronic data storage device of claim 1 or 2, wherein the electronic data storage device is configured to allow data write access to the predetermined data storage portion only by authorized devices.

4. The electronic data storage device of claim 3, wherein the electronic data storage device is configured to:

receiving a write request, the write request including address data associated with the predetermined data storage portion and an identifier of a writing device;

authenticating the writing to the device based on the identifier; and

writing data to said predetermined data storage portion if, but only if, said authentication indicates that said writing device is an authorized device.

5. A cartridge for storing and dispensing liquid for use with an inkjet printer, the cartridge comprising:

a reservoir defining an interior space for storing the liquid;

an outlet for dispensing the liquid; and

the electronic data storage device of any of claims 1-4.

6. An ink jet printer comprising the cartridge of claim 5.

7. Inkjet printer according to claim 6, characterized in that the inkjet printer is a continuous inkjet printer.

8. The inkjet printer of claim 7, comprising a controller, wherein the controller is configured to:

receiving data from the electronic data storage device; and

controlling operation of the inkjet printer based on the received data.

9. The inkjet printer of claim 8, wherein controlling the operation of the inkjet printer based on the received data further comprises:

receiving sensor data; and

controlling the operation of the inkjet printer based on the sensor data.

10. Inkjet printer according to any one of claims 6 to 9, comprising an electronic data storage device according to claim 3 or claim 4, wherein the inkjet printer is an authorised device.

11. An inkjet printer comprising a controller, the inkjet printer configured to receive:

a removable module comprising an electronic data storage device storing data regarding operation of the removable module, and at least one member selected from the group consisting of: filters, fluid dampers, valves, pumps, gas sensors, drop generators, piezoelectric oscillators, charging electrodes, deflection electrodes, and channels; and

at least one cartridge;

wherein the controller is configured to:

receiving data from the electronic data storage device, wherein the electronic data storage device is an electronic data storage device according to any of claims 1-4; and

controlling operation of the inkjet printer based on the received data.

12. The inkjet printer of claim 11, wherein the inkjet printer is configured to receive a plurality of removable modules, each of the plurality of removable modules including a respective electronic data storage device storing data regarding operation of a respective one of the plurality of removable modules, each of the plurality of removable modules further including a member selected from the group consisting of: filters, fluid dampers, valves, pumps, gas sensors, drop generators, inkjet printing nozzles, piezoelectric oscillators, charging electrodes, deflection electrodes, and channels.

13. The inkjet printer of claim 12, wherein the controller is configured to:

receiving data from each of the electronic data storage devices; and

controlling operation of the inkjet printer based on the received data.

14. The inkjet printer of any one of claims 11 to 13, wherein controlling operation of the inkjet printer based on the received data comprises configuring operation of the inkjet printer based on the received data.

15. An inkjet printer according to any one of claims 11 to 13, wherein said at least one cartridge further comprises an electronic data storage device.

16. The inkjet printer of claim 15, wherein the controller is configured to:

receiving data from the electronic data storage device associated with the at least one cartridge; and

controlling operation of the inkjet printer based on the received data.

17. The inkjet printer of claim 16, wherein controlling the operation of the inkjet printer based on the received data further comprises:

receiving sensor data; and

controlling the operation of the inkjet printer based on the sensor data.

18. The inkjet printer of claim 15, wherein the controller is configured to:

receiving data from a first electronic data storage device of the at least one cartridge and a second electronic data storage device of one of the removable module or the removable module; and

controlling operation of the inkjet printer based on the received data.

19. The inkjet printer according to any one of claims 11 to 13, wherein:

the removable module or one of the removable modules and/or the electronic data storage device of the cartridge is configured to allow data write access to the predetermined data storage portion only by authorized devices; and

the electronic data storage device is configured to determine whether the controller is an authorized device and to allow data write access by the controller to the predetermined data storage portion if, but only if, the controller is an authorized device.

20. The inkjet printer according to any one of claims 11 to 13, wherein:

the received data from the electronic data storage device storing data relating to operation of the removable module comprises data representing properties of inkjet printing nozzles associated with a printhead of the inkjet printer; and

controlling operation of the inkjet printer based on the received data includes generating modulation signals for the inkjet printing nozzles based on the received data.